1. Field of the Invention
This invention relates generally to a device for taking a sample of tissue cells from a body and more particularly a syringe for taking a sample of subcutaneous tissue cells from a body.
2. Description of the Prior Art
Such a device is known from International patent application WO 88/01882. The pulling means for exerting a force on the plunger in the direction away from the coupling element are formed by a holder wherein a disposable injection syringe can be accomodated. A first holder part of this known holder comprises a hand grip with a support connected thereto at a distance by guiding rods for the second holder part into which the cylinder of a disposable injection syringe with the finger rest protruding transversely thereto can be clamped fixedly. The second holder part is provided with an opening in which can grip two fingers of a hand holding the hand grip. Using an injection syringe arranged in this holder a suction action can be applied instead of the usual injecting action. Such a suction action is for example applied in taking a sample of cell material, in particular for the purpose of cytological testing. This testing can be used for determining whether a tumour is benign or malignant. For the collection of the cell material the needle of the injection syringe is inserted into the tumour after which the plunger of the syringe is drawn out so that an underpressure is created in the syringe and an amount of cell material is sucked into the needle. It is usual in collecting the cell material to move the needle back and forth a number of times so that sufficient cell material is released. The quantity of the collected material is otherwise usually very limited and then substantially to the capacity of the needle itself.
In order to avoid the material being drawn into the cylinder forcibly by through-flowing air and becoming so spread out there that it is no longer usable for the test, the underpressure must first be neutralized again by moving back the plunger before removing the needle.
The known holder is awkward in use. On withdrawal of the plunger a cramped hand position arises which either makes difficult a sensitive and controlled guidance of the injection syringe needle or makes it impossible. Moreover, the distance from the hand to the area where the needle is inserted is great so that precise and sensitive handling is also made difficult as a result. Further, the assembly of holder with disposable injection syringe is bulky and in the position of use is in fact held in the same position as a pistol, which has an at least disturbing effect on the patient being treated.